Yamaha YZ125-250 (1988-1993) & WR250Z (1991-1993) Motorcycle Service Repair Manual Description Clymer motorcycle repair manuals are written specifically for the do-it-yourself enthusiast. From basic maintenance to troubleshooting to complete overhaul Clymer manuals provide the information you need. The most important tool in your tool box may be your Clymer manual get one today.Every Clymer manual contains hundreds of original photographs and illustrations developed from a complete disassembly and assembly of a motorcycle. This in addition to extensive research allows Clymer to achieve an unmatched level of detail accuracy and clarity.The step-by-step instructions and two-column text with large print are user-friendly. Bold figure numbers make it easy to quickly match instructions with illustrations and photos. Thumb-tabbed chapters numbered table of contents and an extensive index make it possible to locate the desired section quickly. Contents This Yamaha motorcycle manual is 488 pages. QUICK REFERENCE DATA CHAPTER ONE / GENERAL INFORMATION Manual organization / Notes cautions and warnings / Safety first / Service hints / Washing the bike / Torque specifications / Fasteners / Lubricants / RTV gasket sealant / Threadlock / Parts replacement / Optional parts / Basic hand tools / Precision measuring tools / Special tools / Fabricating tools / Mechanic s tips / Ball bearing replacement / Oil seals / Safety / Specifications CHAPTER TWO / TROUBLESHOOTING Operating requirements/ Troubleshooting instruments / Starting the engine / Starting difficulties / Engine starting troubles / Engine performance / Engine / Engine noises / Two-stroke pressure testing / Fuel system / Ignition system / Clutch / Transmission / Drive train noise / Front suspension and steering / Rear suspension / Frame noise / Brakes / Specifications CHAPTER THREE / LUBRICATION MAINTENANCE AND TUNE-UP Pre-ride checklist / Maintenance schedule / Tires and wheels / Lubricants / Cleaning solvent / Engine lubrication / Periodic lubrication / Transmission oil level check and change / Front fork oil change and oil level adjustment / Drive chain lubrication / Swing arm bearing assembly lubrication / Relay arm and connecting rod lubrication / Kickstarter spline lubrication / Front fork dust and oil seal cleaning and lubrication (1989-on) / Periodic maintenance / Drive chain cleaning and adjustment / Clutch adjustment / Throttle cable adjustment / Air filter service / Fuel valve cleaning / Sprocket bolt tightness / Coolant change / Engine tune-up / Cylinder head nuts torque / Spark plug / Ignition timing (CDI) / Carburetor idle speed adjustment / Idle speed and mixture adjustment / Carbon removal / Storage / Specifications CHAPTER FOUR / ENGINE TOP END Engine principles / Engine lubrication / Cleanliness / Servicing engine in frame / Cylinder head / Cylinder and power valve / Piston wrist pin and piston rings / Reed valve assembly / Engine break-in / Specifications CHAPTER FIVE / ENGINE LOWER END Servicing engine in frame / Engine / Engine sprocket / Countershaft oil seal replacement / Crankcase and crankshaft / Specifications CHAPTER SIX / CLUTCH / KICKSTARTER AND EXTERNAL SHIFT MECHANISM Right-hand crankcase cover / Clutch cover / Clutch release mechanism / Clutch release arm / Exhaust governor assembly / Clutch / Clutch service / Clutch inspection / Primary drive pinion gear / Clutch cable / Kickstarter and idler gear / External shift mechanism / Specifications CHAPTER SEVEN / TRANSMISSION AND INTERNAL SHIFT MECHANISM Transmission operation / Transmission troubleshooting / Transmission / Transmission overhaul / Transmission inspection ...